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I offer a crazy energy idea about which I've fantasized: The Salton Sea.

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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 01:03 PM
Original message
I offer a crazy energy idea about which I've fantasized: The Salton Sea.
Edited on Tue Dec-27-05 01:06 PM by NNadir
People who may be familiar with me know that in the current global climate change crisis, I mostly favor those forms of GHG free energy that have proved to work on scale, which more or less limits me to favoring nuclear, wind - and to the very limited extent it is available - geothermal energy. I also believe that solar concentrator plants - which are thermal plants - are worth some serious development in certain locales where they work well.

One of the big drawbacks to wind energy is the necessity for maintaining - at great expense - a back up capacity for when the wind doesn't blow and for solar plants, the inability to work on demand or to create energy reserves.

Still, like many people, I have my share of crazy ideas about energy and for what it's worth, I thought I'd share them here.

East northeast of San Diego, in California, is the Imperial Valley - called the "salad bowl" of the United States because it provides much of the lettuce and tomatoes that appear on American tables in winter. The Imperial Valley is actually a desert and as is often the case out west, the large agricultural output of the Valley is a total function of irrigation. California uses part of its share (and as it turns out the shares of other states) of Colorado River water to irrigate salad growing fields.

Many people may be aware that the Imperial Valley, like Death Valley, is actually below sea level. As California is being geologically ripped apart in the unstoppable adventure of plate tectonics, some areas between large faults, in this case the southern end of the San Andreas and the San Jacinto and Elsinore faults, are actually sinking. The Imperial Valley is actually part of the Salton Trough, a huge sunken block of rock that once defined the upper end of the gulf of California. Deposits of debris from the Colorado delta has actually shut off the northern end of the Gulf from the Southern end. Ultimately the isolated portion of the Gulf, which is subject to little rainfall, dried out, forming a huge sub-sea level basin. Many times in the last several millennia, the Colorado has drained into the basin, filling a huge inland lake, but as the river meandered the lake alternately dried and reformed. Several thousand years ago, the valley dried yet again, and up until the early twentieth century, the valley was completely dry, with a huge dry lake basin on its northern most end.

Today one can drive through the valley and see whimsical lines drawn on high up on silos and other structures marking sea level.

In 1905 an irrigation system designed to irrigate the valley - to create the state of affairs that we now have with a huge agricultural industry there - failed during flooding and began to fill the Imperial Valley completely. It took two years, and a herculean engineering effort to staunch the flow. Thereafter a new inland sea was formed, the Salton Sea. The Sea did not evaporate completely as it's previous natural incarnations had, but has been maintained since by the inflow of agricultural runoff water, all of which has been derived from Colorado River water - almost none of which ever makes it Mexico or to the gulf of Mexico in modern times.

The sea takes in about 1.6 billion cubic meters of water per year, which is more or less exactly counterbalanced by evaporation. The relative rates vary, and the sea shore is not completely stabilized. One can see old resorts that are now in the sea and not at its shoreline. The surface of the sea is more than 70 meters below sea level. If, instead of Colorado River water, the sea were balanced by seawater coming in from an outlet to the sea, this evaporation rate would produce about 1.1 petajoules of energy (1 petajoule = 10^15J) or weighted over a year of average power, a relatively modest 35 MW. However if recovered, this would all be solar energy. Although the energy output is trivial on the scale of coal plants, this would actually represent a rather large solar plant, since, in spite of much crowing and carrying on, only a tiny fraction of solar plants are actually this large. (Some of this energy - though certainly not all of it - may already be recovered through the coupling of small hydroelectric plants to the irrigation system. I have no idea if this is the case.)

Interestingly enough, because of the geological activity associated with being on the boundary between the North American (tectonic) Plate and the Pacific Plate, the the Salton basin actually contains significant geothermal resources. (These are real geothermal resources - not heat pumping schemes involving stored heat in ground water that are sometimes sold as "geothermal" resources.) The entire Salton basin enjoys this resource. The Mexican city of Mexicali uses the Cerro Prieto geothermal field to produce 630 MWe of power to supply its population of almost 1 million people. The heat is transferred using brines, which have a higher heat capacity than fresh water, the brines evaporating off leaving a residual of salt and silica.

In the American portion of the basin (initially Mexican territory that was militarily occupied by the United States in 1846 and never returned) a number of geothermal fields also operate. These currently produce 326 MWe from 10 facilities. Another facility is proposed that will produce 185 MWe, using 361,000 cubic meters of fresh water provided from the Colorado River by the Imperial Valley Irrigation district.

We see from this link discussing Salton Sea Geothermal district http://www.energy.ca.gov/sitingcases/saltonsea / that the Salton Sea Known Geothermal Resource Area comprises almost 101,000 acres (excuse the English units) and will be, upon completion of the new project, only 10% developed. From the figures from the link we can see two things. One is that the geothermal potential of the area amounts to about 5,000 MWe, the equivalent of about four or five nuclear plants. The other is that the production of this power would require about 10 million cubic meters of water, since from the figures provided for the new plant, we can see that each megawatt of power consumes through evaporation, about 2000 cubic meters of water. In other words, if this water were obtained from the Salton Sea itself the evaporation rate could be increased by 0.6%, a small, but significant number.

The evaporation of water from the Salton Sea has an interesting consequence. The Colorado River is important to continental salt flows. The existence of fresh water on continents depends very much on the transports of salt from weathered rock to the sea and like all rivers, the Colorado is a large part of this process. In fact one mechanism for desertification of productive agricultural land involves the long term use of irrigation. "Fresh" water sprayed on fields carry small amounts of salts, which are concentrated by evaporation/transpiration. Ultimately the land itself becomes quite saline and the possibility of growing anything there becomes important. Everything dies, and the salts and topsoil are blown away never to recover. (This process is thought to have played a role in North Africa, which was once the granary of the Roman Empire.) Since the Salton Sea has no outlet, the continental salts formerly brought to the sea in the Gulf of California now end up in the Salton Sea. The salinity of the sea is rising rapidly and is now 25% greater than that of the Pacific Ocean. The Salton Sea has been stocked with various kinds of ocean going fish, notably Tilipia. The opportunity for commercial fishing there was historically rather large. However the increases in the salinity of sea, coupled it is believed with the consequences of chemistry of agricultural run-off, has lead to huge amounts of die-off of fish and the birds who feed on them.

This is somewhat tragic because the destruction of wetlands in California in service to its huge population of hominid apes has made the Salton Sea one of the most important stops for migratory birds. It is believed that the elimination of the sea will have rather dramatic negative consequences on the bird population. About half of the species of birds known in North America can be seen in the Salton Sea area.

Several methods, evaporation ponds and the like, have been sought to deal with the salinity issue - but most of these proposals are very expensive and would involve 100's of millions of dollars. Even though if these proposals were funded, they would involve the output of considerable energy. The salt would have to be removed either by truck or rail or else placed in a huge salt landfill. The United States currently produces about 43 million metric tons of salt for various purposes - most of which involve the chemical industry, road salt and the like. Almost the entire salt industry could be provided by evaporation of an amount equivalent to the evaporation of 1 billion cubic meters of the salton sea - if the transport and economics allowed - which probably it doesn't.

Besides it's geothermal and salt resources, the area around the Salton Sea - as anyone who has been to the Southern California desert can tell - there are considerable wind resources in the area. Wind farms do indeed exist in the area, but again the potential is not fully realized. Moreover, as is always the case with wind, as already mentioned, this power is not always available at peak moments.

Also, the valley has considerable solar resources inasmuch as the weather is almost eternally sunny. To my knowledge, few solar thermal plants exist in the area, even though the Salton sea waters may provide a rather large heat sink for raising the efficiency of solar collector plants, and an opportunity to provide further opportunities for evaporation.

However there is no assurance that the sea can in fact survive. The water wars of the West have just begun. California takes more water than it is allocated from the Colorado, because other states have not called for their "fair" share. The water demands of California's urban hominids, those who inhabit San Diego and LA - and who represent huge voting blocks - does not bode well for the agricultural interests of the Imperial Valley - broad American interest in salads notwithstanding.

Suppose though that some of the off peak wind energy, off peak geothermal, and excess solar were stored by pumping water out of the Salton Sea to locations at higher altitudes? In fact, suppose one were to pump the water is a series of (saline) dams and reservoirs right over the mountains with an outlet draining into either the California Coast or the Gulf of California? The salinity problem of the Salton sea would of course be solved, offset by some energy losses owing to the evaporation from these salt water reservoirs. But what if at the same time sea water pumped out were matched by sea water that came in? Under these conditions, one could obtain energy timed precisely for the moments of peak demand. The salt balance of the Sea could be re-established close to the value of ocean water.

Moreover if the water removed from the sea were not pumped out, but rather sucked out, a side product would be desalination. A column of water at normal atmospheric pressure can be made to rise about 10 meters, after which it boils at reduced pressure, lowering its temperature. It is possible to imagine a series of compressors/vacuum pumps that store energy in the form of compressed air (removed from the portion of air soluble in sea water) and fresh water. The compressed air could be used to pump water (compressed air will drive water more than 10 meters up against a vacuum) when desired, or to run air compressor driven generators, and the fresh water that condenses in the tank (under pressure and cooling) could be separated and spread on agricultural fields below sea level, where it will evaporate, producing yet more energy. Moreover the waste heat of compression could in theory be used to enhance evaporation of the brines - recovering even more energy. The cooled brines obtained from the sea water could either be evaporated at geothermal sites (where the low temperatures would give an efficiency boost) or pumped to the sea at moments of low energy demand, providing for stored energy (in the form of gravitational potential from inflowing seawater that can be later accommodated in the sea).

The depth of the sea, and the location of the shoreline could be managed, restoring a recreation industry that has been problematic because of fish die offs, flooding, and retreat of the shoreline.

How would we bring sea water in though? Two possibilities suggest themselves, one less crazy than the other. The first is simply to bring water in through Mexico from the Gulf of California in a series of canals coupled to hydroelectric facilities. Every kg of water that evaporates once at the Salton Basin floor would represent a solar energy boost, including that of desalinated water used for irrigation, sprayed on the fields and evaporated through transpiration. Another (crazier) possibility is to drill a tunnel under the mountains connecting the sea to the Pacific Ocean. On could, under these circumstances, build a series of inland seas, controlled by dams and hydroelectric stations. Since the area is a major earthquake zone, one could create a safety valve for cases of dam failure represented by a few siphons, wherein the tunnel would be constructed to rise in a few places, a few meters above sea level. One could break the siphons simply by introducing air, and re-establish them by pumping the siphon breaking air out. The cost of such a tunnel can be estimated by the cost of drilling the Chunnel that now connects France and the UK. This passage cost about $10 billion dollars. This is a large investment, but one certainly imagines that it could be recouped as well as the cost of any power facility can. A side product would be a number of reservoirs in which sea food or other sea products could be grown. In addition, a chemical industry could be created via access to the salts, including sodium chloride but various other elements as well. Indeed one could use this system to store energy from anywhere else it is produced in the grid. The nuclear facilities of Arizona, wind farms in Northern California, solar plants in Palm Springs.

This is, then, my crazy idea which I envision as a win-win-win-win, if improbable. I just felt like sharing it.
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CabalPowered Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 01:19 PM
Response to Original message
1. For starters, I didn't know the sea ever existed..
That's very interesting. I'm a little confused about this part.. how does evaporation represent a solar energy boost? Also, in your section of bringing water in from Mexico.. I've always thought at some point California is going to need some gargantuan desalinization plants to provide enough fresh water for the population. In that regard, I've always considered Ocean Thermal Energy Conversion as a good way to generate electricity and also do inline desalinization. Another byproduct would be the availability of high-saline water or the ability to deposit salts.
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 03:18 PM
Response to Reply #1
5. Please see post #4 to answer your immediate question.
I am not familiar with ocean thermal energy conversion. I think I may have heard of something like it, but I'm not sure of the details. If you could explain it, it would be enlightening.
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CabalPowered Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 03:46 PM
Response to Reply #5
7. This is a good write up on OTEC
http://www.nrel.gov/otec/what.html

In short.. extract energy from temperature differences in the ocean column. The concept requires a loop of pipe that extends from the top of the ocean to the bottom of the ocean, or where the coldest water is. Using a medium, such as antifreeze, energy can be collected as the medium moves up the column into warmer water. The warmer water heats the medium and that energy can then be extracted for electricty or any other purpose, such as desal. There's a demo plant in Hawaii that was built in the late 70's/early 80's and is still running and producing electricity. The more modern designs include desal as a byproduct process. Others argue that with such an infrastructure, new ways of ocean farming could be done on the coast with access to cold, high saline water..
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 04:15 PM
Response to Reply #7
8. I'm still weak on the details, but it seems to work in some locations.
Edited on Tue Dec-27-05 04:15 PM by NNadir
According to the web link you've provided the areas of application require a 20C stable thermal gradient and that such regions are mostly located in tropical areas. California seems not to be in that area although much of the US gulf coast is. This map is from your link:



For some reason the NREL has stopped doing research on this application. If the strategy is viable, that is unfortunate.

Thanks for your information.
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CabalPowered Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 05:30 PM
Response to Reply #8
9. Actually the DOE budget this year restarted the
OTEC research. You wouldn't know it looking at their website but they are restarting research. The NREL folks are a bit behind the times. I'm a little fuzzy on the new designs but I guess there's a huge improvement with closed loops systems over the classic open loop systems. But you are correct, there is less potential on the west coast. But if you assume that you have to do some desal, then you're going to need a LOT of juice, as that process is energy intensive. Whatever you can extract from OTEC is better than putting in new coal/nuclear plants. Then there's the additional bonus of the infrastructure itself, from methane clathrate extraction to sea farming, research, CO2 dumping. Frankly, I don't see any other technology that can come close to matching the potential of OTEC. :cheers:
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 05:56 PM
Response to Reply #9
10. I don't see methane clathrate extraction as a good thing.
The last thing the world needs now is more methane, especially were the methane only partially extracted and were partially released.

I'm sure that this technology has some bugs. There are lots of things that sound good, but don't actually deliver very much. This is hardly a proved industrial scale technology. According to the link, there is a good deal of research needing to be done, including making 5 foot diameter PVC pipe.

I would certainly not forestall building any kind of capacity that is GHG free while waiting for this system to be practical and widely usable. Neither would I wait in California to do so while my elaborate Salton Sea scheme were produced. We must have nuclear plants, the more and the sooner the better.
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CabalPowered Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 07:09 PM
Response to Reply #10
11. In clarification
I wouldn't consider methane clathrates either unless the technology to capture and inject/dump CO2 was fully developed and not horribly cost prohibitive. Also to consider, I read last night in January's Wired that an article will be coming out that indicates trees have a CO2 saturation point. At some point we're going to have to consider CO2 dumping. The last thing any of us wants is a methane burp from the ocean. Unfortunately I think with this year's revelations that the thermohaline circulation is slowing and upwelling diminishing, a burp could be close.

OTEC is not a near term solution and will require significant investment, but considering the actual impact per watt generated, OTEC stands behind fusion in attractiveness... IMHO. Until these technologies are near maturity, I think the trick is going to be adopting alternatives that are appropriate for the geography and climate. Like your proposal, site specific. My favorite for a near term solution includes stringing thousands of wind turbines along the Aleutian islands and connecting them to giant electrolysis plants in Alaska and piping hydrogen to the mainland.

And with all due respect, I will never consider nuclear a solution. As it appears we are at odds on that topic, I don't see what good any discourse would do for us on that topic.

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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 08:44 PM
Response to Reply #11
12. With all due respect, I am very glad that your considerations will NOT
Edited on Tue Dec-27-05 08:51 PM by NNadir
prevail.

Whether you would consider nuclear energy a solution, the rest of the world has done so and begun to act on the matter. Even the United States, a country where deliberate energy ignorance is culturally codified, the nuclear industry is proposing a 10 to 15% capacity and that is just the announced increase in 2005. Moreover the rest of the planet is proposing an increase in this capacity of about 38% if one includes reactors under construction, on order, and under proposal. http://www.world-nuclear.org/info/reactors.htm This is a good thing. Finally realistic thinking is triumphing over mysticism. It may prove to be too little, too late, but it is the only chance we have.

Either additional nuclear capacity will be built or a huge fraction of the earth's population will die and a huge portion of its ecosystems will be destroyed. This is very, very, very simple and very, very, very clear. What is also clear is that the matter has become an important ethical issue.

CO2 "dumping" is exactly what the world does now: The dump is the atmosphere. Here's some news "hot" off the presses: It's killing us. No other type of dump other than the atmosphere is even contemplated that could handle the seven billion tons of carbon dioxide that the United States alone dumps. There isn't a lot of time to deal with this extant "dumping." Thus it is urgent that we switch from trying to find more methane to preventing the use of all energy related methane. Methane is an enormously dangerous fuel as the climatic events of the last several years have clearly demonstrated graphically in a way that could not and should not be missed.

It is fine to appeal to mystical fanciful technologies and wishful thinking that, for instance, my Salton Sea scheme represents. It's even fun. I note that at least the Salton Sea scheme, wishful thinking though it may be, does not involve a single technology requiring huge amounts of research. One could in theory begin building it tomorrow if it were funded. Geothermal plants are known and operate. Tunnels and or canals going great distances have been built. Wind farms exist. Hydroelectric plants provide almost as much energy as nuclear power. Desalination technology including flash (low pressure) distillation provides water in many places on earth. Even solar concentrator thermal plants have been built. The technology of irrigation is thousands of years old as is the technology of water pumping. All of these technologies operate on an industrial scale in many places at a profit. Still, all this acknowledged, I would never dream on moral grounds of opposing new California nuclear plants because my Salton Sea scheme sounds so very cool in my own estimation. This is because I am a scientist as well as an environmentalist. Every single nuclear plant that operates or is built in California increases the odds of human survival. Using my education, I have made it my business to comprehend important human issues like risk analysis.

It is not ethical, given the state of the world, to pretend that the world can wait either for OTEC technology, which exists on a pilot scale only, or that the world can afford the status quo. We must have nuclear power, if only because it is the safest form of continuously deliverable energy known. www.externe.info . I note that no one has been killed by commercial nuclear operations in the United States since the industry was founded. This is definitively not the case with respect to methane.

I really don't write here to convince particular individuals of anything, and I never agree to cut off a particular discussion because of a claim that further discourse would do no good. Neither do I consider particular individuals - myself included - to be particularly important. Ideas however are important. A falsehood or distortion that is not confronted is dangerous not just to particular individuals but to humanity as a whole. My game is to point out that people who oppose nuclear power have no option to present for immediate demonstrable scale up, that mostly they rely on extraordinarily optimistic claims for unproved technology or technology that has operated only on a tiny scale. That is the case here. Whether or not you would consider a nuclear solution, you have offered no demonstrated GHG free technology which could be built on a significant scale within this decade. Global climate change is not waiting for the installation of a few megawatts of solar PV cells or for a few OTEC plants in tropical locations. It is happening now.
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CabalPowered Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 07:57 PM
Response to Reply #12
19. Will all due respect, I live down river from the highest
concentration of nuclear reactors in the world. INEL in Southern Idaho. 52 to be exact. This whole area is one big cancer cluster and I've lost friends and family to cancer.
I also have family that has returned from working in the Ukraine, who now live with persistent migraines, suffer from insomnia and have been advised not to have children. You say NIMBY! and I say damn right NIMBY. You say nuclear! and I say hell no!

When I use the word dumping, the connotation implied is in a sink other than the atmosphere, be it the ground or the ocean.

I wasn't aware that the burden was on me to propose a GHG free technology that is feasible in one decade? Instead I was arguing that there are two sides of the equation. Technology to collect and dump CO2 (in a sink other than the atmosphere) would go a long ways in slowing GW.
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 09:39 PM
Response to Reply #19
20. I have lost family and friends to cancer as well.
We had no nuclear reactors on Long Island. On the other hand, I and my children frequently swim right next to the Oyster Creek nuclear station and I never have a headache that could be connected with that pleasant experience. (I do suffer from insomnia, but have done so since my childhood which took place before the widespread use of commercial nuclear power.) I had a job where I was frequently out to restaurants near the Seabrooke nuclear station. The food was quite good and I can't recall every being ill there. For about 4 years I worked with radionuclides daily. I am fine.

Anecdotal claims are completely useless though and are generally the refuge of weak arguments. If you are prepared to prove that the cancers of everyone you know is radiation related, do so. Otherwise, I am unimpressed. Once you are done with your proof, I will ask you to compare how these people you know compare to people who have been killed by carbon monoxide leaks from gas furnaces, or people killed in coal mines, or people who have fatal respiratory diseases as a result of working in coal mines or living near coal fired power plants.

I note that there are many millions of people who have lived in the Ukraine (which is by the way a huge user of very dirty coal) who have children and who don't suffer from migranes and who don't have insomnia. I also note that there are many people in the Ukraine who suffer from health effects from air pollution, chemical contamination, and accidents, notably coal mining accidents, many of which dwarf Chernobyl. The entire country is an ecological basket case owing to unrestrained industrialization in the glorious Soviet Worker's state. I quote this citation from Environmental Toxicology and Chemistry, Vol.19, No.5, pp.1231-1232, (2000), "...We discussed such matters with Dr. Victor Baryakhtar, Vice President for Ukraine's Academy of Sciences. When comparing the ecological consequences of the Chornobyl region to those in the highly industrialized heavily populated areas of eastern and southern Ukraine, he observed, "Northern Ukraine is the cleanest part of the nation. It has only radiation."

http://www.nsrl.ttu.edu/chernobyl/wildlifepreserve.htm

Here is a report on the extraordinarily bad air that may have had as much as your families health as the massive bath of radiation you claim for them: http://gis.esri.com/library/userconf/proc01/professiona...

It is the responsibility of every person to weigh energy alternatives in the age of global climate change since the issue of global climate change is global NIMBY. If you oppose nuclear power on the grounds that you know someone who has died of cancer it is VERY much your burden to propose GHG technology that is available in one decade. Why? Because the status quo kills in much greater quantities than nuclear energy. Because nuclear technology works. It has the lowest impact in the unfortunate unit of deaths per watt of any industrialized energy production scheme, with the exception of wind power. Therefore if you insist on gas and coal, you are demanding that we face a higher risk of premature risk than we would with nuclear energy. To are in short calling for more deaths.

In the last twenty years air pollution has killed much more than the entire population of Idaho and the Ukraine combined. The current estimate for yearly air pollution deaths is 3 million per year. What's more global climate is likely to kill on a much grander scale than it already has done, potentially in the billions.

The issue is one of risk assessment, and does not rest on a claim that any form of energy without risk exists. Risk assessment involves comparing risks, say coal vs nuclear, solar vs. wind, solar vs. nuclear. The European Union has done just this. The report is found here www.externe.info Click on results.

Coal mining is a human disaster of gargantuan proportions. Hardly a month goes by where somewhere in he world (often China) some thousands of people are killed in mining accidents.

In short, burying your head in the sand and attributing causal relationships to illnesses of people you know without proof does not entitle you to put my children's life in danger. I am trying hard to save my children, and I believe that they will have a very poor chance, or no chance, without nuclear power.


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eppur_se_muova Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Feb-26-06 06:38 PM
Response to Reply #7
21. I didn't know there was actually a demo plant.
I may have to drag out some more references to this. They're on that old information technology medium, paper. I was under the impression that later designs called for no antifreeze, but used water vapor at sub-atmospheric pressure for the working fluid (evaporation/condensation cycle).

OTEC is where nuclear was right after WWII -- only slapped-together prototypes, but functioning prototypes.

The cold water piped up from depth would carry enough nitrate to nourish algae as a food source. This has been proposed as a potential base for ocean-going aquaculture.
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bananas Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 12:25 PM
Response to Reply #1
14. The Salton Sea was caused by an irrigation accident
http://www.saltonsea.ca.gov/about/history.htm

In 1901, the California Development Company, seeking to realize the Imperial Valleys potential for unlimited agricultural productivity, dug irrigation canals from the Colorado River. Heavy silt loads, however, inhibited the flow and new residents of the valley became worried. This prompted the engineers to create a cut in the western bank of the Colorado to allow more water to reach the valley. Unfortunately, heavy flood waters broke through the engineered canal and nearly all the rivers flow rushed into the valley. By the time the breach was closed, the present-day Salton Sea was formed.

Instead of evaporating over a period of years, todays Salton Sea is maintained, in large part, by agricultural runoff from irrigation in the Imperial and Coachella valleys.
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bananas Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 12:45 PM
Response to Reply #1
15. Salton Sea on an earthquake map
You can see it's size and location clearly on the "Regional Event Map"
http://eqinfo.ucsd.edu/dbrecenteqs/anza/AZ_R_map.html
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 04:06 PM
Response to Reply #15
18. That's a very nice map.
One can see the depression and the geology of the area very well. When I look it at it, I see a few areas that could serve as high altitude reservoirs.

Thanks.
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Tikki Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 01:19 PM
Response to Original message
2. Hi NN....I remember reading that this area was anticipating....
...a home/business building boom....
http://www.thedesertsun.com/apps/pbcs.dll/article?AID=/...


Tikki
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drm604 Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 01:38 PM
Response to Original message
3. One thing I don't understand...
How would evaporation from the Salton sea generate usable energy?
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 03:15 PM
Response to Reply #3
4. The Salton Sea surface is way below (oceanic) sea level.
This means that if one had access to the sea, one could build a normal hydroelectric type of plant that exploits the difference in height between the Salton sea and the ocean. (This distance is 70 meters.) If the sea didn't evaporate, eventually though the Salton Sea would rise to the level of ocean, inundating the Imperial Valley and eliminating the difference in height. Thus it would no longer be possible to obtain energy from the "falling" water.

The difference in height can only be maintained as long as the Salton Sea remains below oceanic sea level. When water evaporates from the Salton Sea, it is removed, and the difference in height is maintained.

Note that sea water is about 3.5% salt. It is necessary to remove this salt as well as the water. This is why I proposed brine pumps to pump brine out of the sea, possibly after some of the water has been removed in desalination processes.

Brine pumping and ocean dumping is not environmentally neutral by the way. Wherever the outfall exists a local salt gradient will be obtained. This flow must be carefully controlled so as to prevent ecological damage. In any case this would be true of any desalination technology.

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drm604 Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Dec-27-05 03:38 PM
Response to Reply #4
6. Okay, I see what you're saying now.
Thanks!
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Dead_Parrot Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 12:45 AM
Response to Original message
13. I can't decide...
...if you're a certifiable genius, or just certifiable. It obviously couldn't work, but I'll be damned if I can think of a single reason why. Maybe you should slap a patent on it and sell it to Israel to cure their Dead Sea Blues...
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happyslug Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 01:22 PM
Response to Reply #13
16. Something like it has bene proposed for the Dead Sea.
Similar proposals have been for the Quttar Depresion between Egypt and Libya and to save the Arel Sea in Central Asia (Through the Arel Sea would use Fresh water diverted from the Ob and the Volga Rivers NOT the oceans).

On both the Dead Sea and Qattra Diversions plasn:
http://www.unu.edu/unupress/unupbooks/80858e/80858E0a.h...
http://www.osti.gov/energycitations/product.biblio.jsp?...

On the Aral Sea Diversion:
http://www.newscientist.com/article.ns?id=dn4637
http://www.ecoworld.org/Home/Articles2.cfm?TID=354
http://www.american.edu/TED/ice/aralsea.htm
http://web.worldbank.org/WBSITE/EXTERNAL/COUNTRIES/ECAE...

Qattara Depresion:
http://en.wikipedia.org/wiki/Qattara_Depression
http://www.osti.gov/energycitations/product.biblio.jsp?...

Dead Sea electric Generation:
http://www.american.edu/ted/deadsea.htm
http://www.ezekielproject.org/proposal.shtml
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NNadir Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Dec-28-05 04:03 PM
Response to Reply #16
17. You see, if you think you have an original idea, you probably don't.
The very same thing happened to me about 20 years when I thought I had "discovered" the possibility of transmutation of so called "nuclear waste." Actually people had been considering this technology for some time. (I have another idea on that topic which may be original though, damned if I can find anyone who's thought of it.)

My Salton Sea scheme varies in the details, but not in the main conception from the various proposals you have linked. I suppose the big difference from what I propose is that part of my scheme turns the Imperial Valley into a massive battery designed to store, as much as produce, energy.

Thanks for these useful links.
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hunter Donating Member (1000+ posts) Send PM | Profile | Ignore Mon Feb-27-06 11:40 AM
Response to Reply #13
22. Salt water canals are potentially dangerous.
Especially in earthquake prone agricultural areas.

One of the big negatives often brought up in these schemes is the posibility that salt water canals might rupture, thus damaging agricultural land and fresh groundwater supplies. In Israel especially they are always concerned about sabotage.

In any case water politics in the Imperial Valley is extremely complex and not always rational. It would probably be easier to build a nuclear power plant.

The area from the Salton Sea down into the Gulf of California was historically lakes and marshes supplied by the Colorado River. In the area surrounding the Salton Sea you can see a "bathtub ring" on the surrounding mountains caused by a freshwater lake (Lake Cahuilla) that once existed there. This lake was cyclical. During floods the Colorado River would break its banks and fill the lake. Then natural river levies would build up, cutting off the lake, and it would dry up. The last evaporation cycle was complete by 1600. The lake was last full about 900 years ago.

Here's a picture of the area taken from the Space Shuttle:



The Salton Sea is at the top, the Colorado River enters the picture on the right.


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